A body of mass 40kg resting on a rough horizontal surface is subjected to a force P which is just enough to start the motion of the body. If μs=0.5, μk=0.4, g=10m/s², and the force P is continuously applied on the body, then the acceleration of the body is?

Correct option is B. 1m/s²

Given that,
Mass of a body m = 40 kg
μs = 0.5
μk = 0.4
g = 10 m/s²

Since, P is the force which is just enough to start the motion of the body
P = μsN = μsmg

When the body moves under this force, the net force on the body is given by
F = ma = P - f
ma = μsmg - μkN
ma = m(μs - μk)g
a = (μs - μk)g
a = (0.5 - 0.4) × 10
a = 1 m/s²

So, The acceleration of the body is 1m/s²
Hence, B is the correct option.